diff options
Diffstat (limited to 'fs/splice.c')
| -rw-r--r-- | fs/splice.c | 126 |
1 files changed, 25 insertions, 101 deletions
diff --git a/fs/splice.c b/fs/splice.c index 12028fa41def..9bc07d2b53cf 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -136,8 +136,6 @@ error: const struct pipe_buf_operations page_cache_pipe_buf_ops = { .can_merge = 0, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, .confirm = page_cache_pipe_buf_confirm, .release = page_cache_pipe_buf_release, .steal = page_cache_pipe_buf_steal, @@ -156,8 +154,6 @@ static int user_page_pipe_buf_steal(struct pipe_inode_info *pipe, static const struct pipe_buf_operations user_page_pipe_buf_ops = { .can_merge = 0, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, .confirm = generic_pipe_buf_confirm, .release = page_cache_pipe_buf_release, .steal = user_page_pipe_buf_steal, @@ -547,8 +543,6 @@ EXPORT_SYMBOL(generic_file_splice_read); static const struct pipe_buf_operations default_pipe_buf_ops = { .can_merge = 0, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, .confirm = generic_pipe_buf_confirm, .release = generic_pipe_buf_release, .steal = generic_pipe_buf_steal, @@ -564,8 +558,6 @@ static int generic_pipe_buf_nosteal(struct pipe_inode_info *pipe, /* Pipe buffer operations for a socket and similar. */ const struct pipe_buf_operations nosteal_pipe_buf_ops = { .can_merge = 0, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, .confirm = generic_pipe_buf_confirm, .release = generic_pipe_buf_release, .steal = generic_pipe_buf_nosteal, @@ -767,13 +759,13 @@ int pipe_to_file(struct pipe_inode_info *pipe, struct pipe_buffer *buf, goto out; if (buf->page != page) { - char *src = buf->ops->map(pipe, buf, 1); + char *src = kmap_atomic(buf->page); char *dst = kmap_atomic(page); memcpy(dst + offset, src + buf->offset, this_len); flush_dcache_page(page); kunmap_atomic(dst); - buf->ops->unmap(pipe, buf, src); + kunmap_atomic(src); } ret = pagecache_write_end(file, mapping, sd->pos, this_len, this_len, page, fsdata); @@ -1067,9 +1059,9 @@ static int write_pipe_buf(struct pipe_inode_info *pipe, struct pipe_buffer *buf, void *data; loff_t tmp = sd->pos; - data = buf->ops->map(pipe, buf, 0); + data = kmap(buf->page); ret = __kernel_write(sd->u.file, data + buf->offset, sd->len, &tmp); - buf->ops->unmap(pipe, buf, data); + kunmap(buf->page); return ret; } @@ -1528,116 +1520,48 @@ static int get_iovec_page_array(const struct iovec __user *iov, static int pipe_to_user(struct pipe_inode_info *pipe, struct pipe_buffer *buf, struct splice_desc *sd) { - char *src; - int ret; - - /* - * See if we can use the atomic maps, by prefaulting in the - * pages and doing an atomic copy - */ - if (!fault_in_pages_writeable(sd->u.userptr, sd->len)) { - src = buf->ops->map(pipe, buf, 1); - ret = __copy_to_user_inatomic(sd->u.userptr, src + buf->offset, - sd->len); - buf->ops->unmap(pipe, buf, src); - if (!ret) { - ret = sd->len; - goto out; - } - } - - /* - * No dice, use slow non-atomic map and copy - */ - src = buf->ops->map(pipe, buf, 0); - - ret = sd->len; - if (copy_to_user(sd->u.userptr, src + buf->offset, sd->len)) - ret = -EFAULT; - - buf->ops->unmap(pipe, buf, src); -out: - if (ret > 0) - sd->u.userptr += ret; - return ret; + int n = copy_page_to_iter(buf->page, buf->offset, sd->len, sd->u.data); + return n == sd->len ? n : -EFAULT; } /* * For lack of a better implementation, implement vmsplice() to userspace * as a simple copy of the pipes pages to the user iov. */ -static long vmsplice_to_user(struct file *file, const struct iovec __user *iov, +static long vmsplice_to_user(struct file *file, const struct iovec __user *uiov, unsigned long nr_segs, unsigned int flags) { struct pipe_inode_info *pipe; struct splice_desc sd; - ssize_t size; - int error; long ret; + struct iovec iovstack[UIO_FASTIOV]; + struct iovec *iov = iovstack; + struct iov_iter iter; + ssize_t count = 0; pipe = get_pipe_info(file); if (!pipe) return -EBADF; - pipe_lock(pipe); - - error = ret = 0; - while (nr_segs) { - void __user *base; - size_t len; - - /* - * Get user address base and length for this iovec. - */ - error = get_user(base, &iov->iov_base); - if (unlikely(error)) - break; - error = get_user(len, &iov->iov_len); - if (unlikely(error)) - break; - - /* - * Sanity check this iovec. 0 read succeeds. - */ - if (unlikely(!len)) - break; - if (unlikely(!base)) { - error = -EFAULT; - break; - } - - if (unlikely(!access_ok(VERIFY_WRITE, base, len))) { - error = -EFAULT; - break; - } - - sd.len = 0; - sd.total_len = len; - sd.flags = flags; - sd.u.userptr = base; - sd.pos = 0; - - size = __splice_from_pipe(pipe, &sd, pipe_to_user); - if (size < 0) { - if (!ret) - ret = size; - - break; - } - - ret += size; + ret = rw_copy_check_uvector(READ, uiov, nr_segs, + ARRAY_SIZE(iovstack), iovstack, &iov); + if (ret <= 0) + return ret; - if (size < len) - break; + iov_iter_init(&iter, iov, nr_segs, count, 0); - nr_segs--; - iov++; - } + sd.len = 0; + sd.total_len = count; + sd.flags = flags; + sd.u.data = &iter; + sd.pos = 0; + pipe_lock(pipe); + ret = __splice_from_pipe(pipe, &sd, pipe_to_user); pipe_unlock(pipe); - if (!ret) - ret = error; + if (iov != iovstack) + kfree(iov); return ret; } |